Material handling apparatus



Mar 1 1966 JOHN w. KAPPEN ALSO KNOWN AS JNO. W. KAPPEN MATERIAL HANDLING APPARATUS 4 Sheets-Sheet 1 Original Filed May 4., 1959 mum ALSO KNOWN AS JNO. W. KAPPEN MATERIAL HANDLING APPARATUS Original Filed May 4. 1959 Mar 1 1966 JOHN w. KAPPEN 4 Sheets-Sheet 2 Q INVENTOR.

uo/m/ w KflPP'A/ BY g flTTOkA/f) March 15, 1966 JOHN w. KAPPEN 3,240,369

ALSO KNOWN AS JNO. w. KAPPEN MATERIAL HANDLING APPARATUS Original Filed May 4., 1959 4 Sheets-Sheet 5 N EP fl mm w N M d 4 2 E\ u w, M f f d.

E w J1 n) .1 M )W 3 fi k\ n 4 L 2 March 15, 1966 JOHN w. KAPPEN 3,240,369

ALSO KNOWN AS JNO. W. KAPPEN MATERIAL HANDLING APPARATUS Original Filed May 4, 1959 4 Sheets-Sheet 4 4| 32 f I I 1 llhll 30 2. B of Truck V A Base of Truck INVENTOR JOHN W. KAPPEN United States Patent 3,240,369 MATERIAL HANDLING APPARATUS John W. Kappen, Dayton, Ohio; Frieda E. Kappen, ad-

ministratrix of the estate of said John W. Kappen, also known as Jno. W. Kappen, deceased Continuation of application Ser. No. 810,869, May 4, 1959. This application Nov. 13, 1962, Ser. No. 237,400

7 Claims. (Cl. 21475) This invention relates to the art of material handling, and particularly to transport and delivery vehicles equip ped for a facile system of loading, stowing and unloading cargo and material holding pallets. This is a continuation of application Serial No. 810,869, filed May 4, 1959, no]! abandoned.

A primary purpose of the invention is to conserve time and space and minimize labor of loading and unloading saparable allotments of goods. To such end separate consignments are arranged within the storage compartment of the vehicle in superposed tiers for travel movement to and from a power operated elevator embodied in the vehicle and by which the assorted lots of goods as supported on individual pallets are raised and lowered, with a minimum effort of the driver or operator,

The object of the invention is to simplify the construction as well as the means and mode of operation of material handling apparatus, whereby such apparatus may not only be economically manufactured, but will be more efiicient and satisfactory in use, adaptable to a wide variety of applications, and be unlikely to get out of order.

A further object of the invention is to achieve material handling apparatus as described in which the use of the doors closing the rear of the vehicle storage compartment to support and to guide the loaded pallets is obviated.

Another object of the invention is to provide an elevator mechanism in equipment as described which is self storing in that it is adjustable to an inobtrusive secure position for vehicle running without, however, being detached from or disconnected from the vehicle.

A further object of the invention is to provide improved ease of access to the elevator for loading and unloading of the pallets.

Still another object of the invention is to present an elevator mechanism capable of a wide range of travel, as

well as one obviating interference with movement of a loaded pallet into and out of the transport vehicle.

Still another object of the invention is to provide a generally new mast structure for the elevator mechanism offering advantages of simplified construction and operation as well as facilitating carrying out of foregoing objects. g

Another object is to'improve upon material handling transport vehicles of the prior art, for example as shown in the patent to Black No. 2,635,771, dated April 21. 1953, the instant invention affording specific improvement in variation and kind as compared to Black.

A further object of the invention is to provide a material handling apparatus possessing the advantageous structural features, the inherent meritorious characteristics and the mode of operation herein mentioned.

With the above and other incidental objects in view as will more fully appear in the specification, the invention I intented to be protected by Letters Patent consists of the features of construction, the parts and combinations there- 3,240,369 Patented Mar. 15, 1966 of, and the mode of operation as hereinafter described or illustrated in the accompanying drawings, or their equivalents.

Referring to the accompanying drawings wherein is shown one but obviously not necessarily the only form of embodiment of the invention,

FIG. 1 is a view in perspective showing the rear of a vehicle equipped with the material handling apparatus of the illustrated embodiment of the invention, the vehicle being shown in running condition with the doors to the storage compartment closed and the lift arms of the elevator mechanism folded to a non-operating position;

FIG. 2 is a fragmentary view similar to FIG. 1, with the doors removed and some parts broken away to show details of the elevator mechanism and of the means to mount a removable bulkhead in the vehicle storage compartment;

FIG. 3 is a detail view in cross-section as a guide installed in the storage compartment of the vehicle as a support for one end of the loaded pallets;

FIG. 4 is a detail view of the elevator mechanism, showin the means to locate the elevator in a selected position of vertical adjustment;

FIG. 5 is a view in perspective of a guide as shown in FIG. 3;

FIG. 6 is a detail view showing a support for the lift arms of the elevator when in folded, non-operating position, the support being shown adjusted to an ineffective position assumed in the use of the elevator;

FIG. 7 is a detail view showing a modified connection between one of the lift arms and a tie bar common to the pair of lift arms;

FIG. 8 is a detail view of the connected of FIG. 7 partly broken away to show the means permitting limited motion of parts of the elevator mechanism relatively to the tie bar;

' FIG. 9 is a view similar to FIG. 2 showing a modified form of means to achieve extension and retraction of the elevator mechanism;

FIG. 10 is a fragmentary view in plan, showing substantially'the parts of FIG. 7;

FIG. 11 is a diagrammatic view showing the means to supply hydraulic pressure to the elevator mechanism for raising and lowering thereof,

- FIG. 12 is a detail cross sectional view, showing the nested arrangement of the masts of each mast assembly and the means whereby the inner mast is extensible below the outer mast,

FIGURE 13 is a schematic section view of the mast showing the elevator mechanism in its lowermost position,

- and FIGURE 14 is a schematic section View of the mast showing the elevator mechanism in a raised position.

Like parts are indicated by similar characters of reference throughout the several views.

Referring to the drawings, in accordance with one aspect thereof the invention comprises a unitary material handling apparatus adapted. for mounting to an existing transport and delivery vehicle. In the illustrated instance, the assembly is shown mounted on a truck or truck-trailer having a body 15 supported inelevated relation to ground level by wheels 16. The truck body 15 provides an elongated storage compartment 17 running lengthwise of the body 15 and opening through the rear thereof. The storage compartment is closed when the truck is rigged for running, by doors 18 and 19 which wing to a position of closure with respect to the open end of the storage compartment. The material handling assembly is mounted to the rear of the body in surrounding relation to the open end of compartment 17. It includes gusset shaped mounting plates 21 and 22 dependent from the body 15 to the rear of the wheels 16, Transverse means extend between and interconnect the plates 21 and 22 including a mounting bar 23. Bolted or otherwise secured to the side extremities of the body are vertically extending outer masts 24 and 25, one on each side of the open end of storage compartment 17. On the outer masts are hinges 26 which support the doors 18 and 19 for swinging motion to open and closed positions relatively to the storage compartment. The outer masts'24 and 24 have a formed, channel-like configuration and are disposed in opposing relation to one another so as to present inwardly facing vertically slotted openings 27.

At the bottom of each outer mast, the masts being constructed in like manner, is an externally mounted foot 28 serving as an attachment for one end of a bumper 29, the other end of which is attached to a bracket 31 on the exterior of the outer mast. Also in the bottom of the outer mast, interiorly thereof, is a plate 30 serving as a base for the mounting of the lower end of a hydraulic cylinder 32 which extends upward within the confines of the outer mast and has a piston 33 projecting upwardly therefrom.

The plate 30 is suitably made fast to the outer mast 24 and through it to the body frame, as through a laterally projecting plate 30a. In substantially surrounding relation to the cylinder and piston assembly 32-33 is an inner mast 34, the closed upperend of which is abutted by the outer extremity of piston 33. The inner mast 34 is in sliding telescopic engagement with the outer mast and, it will be understood, is extended and retracted relatively thereto in response to extending and retracting movements of the piston 33 relatively to the cylinder 32.v Thus, an extension of the piston 33 vertically upward from the cylinder 32, as may be effected by the introduction of hydraulic fluid under pressure into the lower end of the cylinder beneath the piston, effects and results in a corresponding elevation or extension of the inner mast 34 which projects upward through the upper end of the outer mast and above the upper level of the roof of truck body 15. The inner mast 34 has a generally rectangular. hollow configuration, received in the outer mast with freedom of vertical relative motion. One of the broad sides thereof bridges the slotted opening 27.

It will be understood that an elevator assembly as described is associated with eaoh mast 24 and 25, there being in each such outer mast an inner'mast and a piston, cylinder mechanism whereby the inner mast is raised and lowered relatively to the truck body. The upper ends of the respective outer masts 24 and 25 may be normally closed, as indicated, by flaps 35 and 36 which are selfclosing and which may automatically be displaced by a rising inner mast, to allow upward projection of the inner masts as shown in FIG. 2.

The inner mast 34, of each of whatmay be considered to be the left-hand and right hand mast assemblies, presents, as shown in FIG. 10, a closed face to the slotted opening 27 of the outer mast. A flange 37, formed integrally with a plate 38, projects into the slotted opening 27 and is secured to the closed face of the inner mast-34. The plate 38 is arranged alongside the mast assembly in generally parallel nearby relation thereto, the flange 37 positioning the. plate in adjacent but spaced relation to the slotted face of the outer mast. Also integrally connected to the plate 38 and extending angularly therefrom in a direction transversely of the longitudinal axis of the body 15 is a bracket arm 39 which extends into interfitting relation with one end of a tie bar 41. The latter extends betweenand interconnects the left hand and right hand assemblies, or, more particularly, the plates 38 connected to and spaced inwardly of the mast assemblies. In the illustrated instance of FIG. 4, the tie bar 41 is attached to the bracket arm 39 in a secure manner precluding relative motion between the tie bar and the slidable masts. Thus, complementary bolt holes 42 are provided in the tie bar and in the bracket arms which are of a size close- 1y to accept bolts (not shown herein). In a modified form of the invention, however, as shown in FIGS. 7 and 8, a tie bar 41a is shown having laterally enlongated bolt holes 42a. The result is that some lost motion is permitted in the connection between the tie bar and the slidable masts so that something less than perfect unison adjustment of the respective masts will not result in binding of the parts.

Each plate 38 further serves as a mount for a lift or guide arm 43 which at its inner end is pivotally connected to the plate 38 by means including a transverse pivot pin 44. The lift or guide arms 43, together with the tie bar 41, make up an articulated arm structure as disclosed in applicants co-pending application Serial No. 764,453, filed September 30, 1958-, now Patent No. 3,040,922, dated June 26, 1962. The pivot pin 44 hereof corresponds to and serves the same function as the pivot pin 5 of the patent. Briefly, the arms serve as the lift elements for direct engagement with the underside of load carrying pallets. In the operation of the elevator mechanism of which the lift arms. are a part, the arms normally project rearwardly from the truck body in parallel relation to one another and perpendicular to or at right angles to the tie bar 41. On the upper edge of each lift arm are sets of guide rollers 45, 46 and 47 providing for anti-friction engagement with the underside of the load carrying surface of the pallets. Normally locked in a projecting position as indicated, each arm 43 may be released through a manipulative control 48 for rocking motion about the pivot pin 44 to a folded position against the rear of the truck body, as indicated in FIG. 1. A further jointed construction in the arm 43 provides for relative swinging motion of an outer portion of the arm about a pivot pin 49, motion of the arm in this instance being in the opposing sense or outwardly through and beyond the perpendicular position shown in FIGS. 2 and 10. Release of the arms for this adjustment is effected through manipulative control 51 at the outer end of the arm and is used to facilitate placement and removal. of a pallet from loading position or to a position of cooperative relation with the lift arms.

The sets of rollers 47, in part comprising the guide arms, are located between the mast assemblies in superposed relation to respective plates, 38. Occupying a laterally intermediate position on the plates 38, the sets of rollers 47 are thus spaced by the flange 37 and by reason of their own location a substantial distance inward from the mast assemblies. The possibility of interfering engagement of the ends of a loaded pallet with the mast assembly thus is minimized. At the same time, however, the guide arms retain a widely spaced relation adapting them to engage and support a pallet near its ends.

In a lowered, folded position of the arms 43 they are permitted to rest upon respective supports 52 and 53 pivotally connected to the previously mentioned stationary cross-bar 23 in a manner to limit downward rocking movement of the supports to the positions as shown in FIGS. 1 and 2. When not in use, the supports 52 and 53 may be rocked upwardly over and forwardly of the crossbar 23 to be out of the path of' the descending tie bar 41 and permit a descent of the assembly comprising the bar 41 and the lift arms 43 below the stored or non-operating position of FIG. 1. A 'cover member 54 also is pivotally connected to the cross-bar 23, and, in the closed up running position of FIG. 1, is rocked rearwardly and downwardly as a protective enclosure for substantial parts of the lift arms 43. The tie bar 41 carries a step 55 by which the operator of the material handling assembly may ride with the elevator mechanism.

FIGURES 13 and 14 show the positioning of the parts as discussed above. FIGURE 13 shows the position of the inner mast 34 when the lift arms 43 are in their lowermost position. In this position the arms 43 are below the base of the truck. FIGURE 14 shows the cylinder 33 in operative condition and shows the mast 34 and the; arm 43 in a raisedposition.

on each side of the storage compartment extending longitudinally therein substantially from end to end thereof. The guides terminate at their one ends at the open end of the compartment 17 at the rear of the body and, as will be understood, it is a function of the lift arms 43 to serve 'as continua-tions or continuing guides outside the compartment; The arms selectively so serve in response to vertical adjustment of the elevator mechanism. Thus the parallel guides on each side of the storage compartment are in a common vertical plane. The associated guide or lift arm 43 is in the same said. plane, by virtue of its attachment to a respective plate 38. Hence upon appropriate selective vertical positioning of the inner masts the arms 43 may be brought into alignment with selected storage compartment guides to act as extensions or continuations thereof. The described arrangement insures a uniform pallet support at all times and under all conditions of load, obviating misalignment of the pallet irrespective of stress and load conditions with the storage compartment guides.

Each of the several guides 56 and 57 comprises a substantially L-sh-aped bracket 58, as shown in FIGS. 3 and 5, secured to the truck and carrying a longitudinally extending channel piece 59 in which is mounted a continuous series of anti-frictional rollers 61. In the laterally extending portion of the bracket 58 are openings 62 alternatively arranged in continuous or intermittent series. These latter define anchoring positions for latch pins 63 on bulkhead members 64 which are selectively installed in the storage compartment to contain a load less than capacity from shifting. The bulkheads are comprised generally of sections of fiat sheet metal reinforced by intersecting bars 65 and 66 and having holders 67 at their corners for sliding retention of the latch pins 63. As indicated, the latch pins 63 are engageable in selected openings 62 of the parallel guides to secure the bulkheads in the storage compartment, there being conveniently two such bulkheads, one in the lower half of the storage compartment and the other in the upper half. A set of perforate brackets 68' extends lengthwise of the storage compartment in the top thereof to provide an anchoring means for the latch pins 63 on the upper edge of the upper one of the bulkheads 64.

The sets of guides 56 and 57 provide supports whereby loaded pallets may be carried in tiers within the storage compartment, as well as providing means by which the pallets may be easily moved from end to end of the compartment for storage and for removal. The pallets are suspended from their ends on respective guides of a set and are delivered to and removed from such guides by the lift arms 43 which make a similar engagement with the pallet. In the use of the material handling apparatus, the lift arms 43 rest in a lowermost position at or substantially at ground level. They are, if necessary, swung outward to permit of the placing of a loaded pallet between the arms with its respective ends in overlying relation to the arms, this position of the pallet being facilitated by the normal mounting thereof on wheels or supports which hold the load receiving surface of the pallet relatively elevated to ground or floor level. With the lift arms underlying the ends of the pallet as described, the elevator mechanism is activated to energize the cylinder and piston assemblies within the respective outer masts 24 and 25. When this occurs, the inner mast 34 begins to extend vertically relatively to the outer masts and relatively to the truck body, carrying upwardly with it the lift arms 43 and tie bar 41. The loaded pallet so is raised from the ground or floor and lifted toward the compartment 17. The lift arms are free to traverse the open end of the compartment 17 and under suitable control are brought to a halt in a position aligning the guides 4547 thereon with a selected set of guides 56 or 57. To aid in this alignment, a stop member 69, in the case of guides 56, or a stop member 71 in the case of guides 57, is swung out to interrupt the movement of a rising lift arm assembly, the stop members being hinged for pivotal movement to the sidewall of the truck adjacent to the masts 24. The sidewalls provide brackets pivoted at 69a for this purpose.

Normally occupying a position as shown in FIG. 2 wherein they are folded inward out of the path of movement of the lift arm assembly, the stop members 69 and 71 are adjustable by hand to an effective position. Each such stop member, as indicated, is formed with a horizontally disposed projecting nose which in the effective position of the stop member lies in the path of bracket arm 39 of the lift assembly. As a result, engagement of the stop members by the lift arm assembly positively arrests the assembly from further upward motion. The arrangement and positioning of the sets of stop members, it will be understood, is such as to locate the lift arms assembly for alignment of the arms 43 with selected sets of guides 56 or 57. So aligned, a loaded pallet may be pushed from the lift arms onto the guides and then to a place of storage in the compartment 17. A reverse operation occurs in the case of unloading. Thus the elevator mechanism is activated to adjust the lift arms 43 into alignment with a selected set of guides 56 or 57. A pallet then is brought out of the truck body along the selected guides therein, rolled out onto the lift arms 43 and then the elevator mechanism is allowed to descend again to ground level where access is had to the pallet for removal.

It will be understood that an aligned position of the lift arms with the compartment guides, once achieved, is maintained during loading or unloading of a pallet, by a continuing application of power to the cylinder and piston mechanism 32-33 suflicient to maintain a thrust engagement of the bracket arms 39 with the nose portions 70 of the stop members.

The hydraulic cylinder and piston mechanism 3233 may be a part of any convenient system for generating and controlling the application of hydraulic pressure. In the illustrated instance this hydraulic generating and applying means is comprised in a package unit mounted as an accessory to the heretofore described element of the material handling assembly at the rear of the truck between the gusset plates 21 and 22. The hydraulic system includes, as shown in FIG. 11, a reservoir 72 holding hydraulic fluid, a motor pump assembly 73 selectively put into operation under convenient driver or operator accessible controls, a hydraulic outlet 74, a line 75 common to the left hand and right hand hydraulic cylinders, branch lines 76 and 77 leading respectively from the common line 75 to the cylinders 32 at the left hand and right hand mast assemblies. Interposed in the line 75 are control elements such as an equalizer valve '78 tending to balance out the effects of an unequal load distribution upon a supported pallet. In the branch lines 76 and 77 are flow control valves 79 and 81 restricting return flow of the hydraulic fluid to permit a gradual lowering of the elevator assembly.

The mast assemblies as described include a direct acting piston and cylinder mechanism as shown in FIG. 2. As seen in FIG. 9 other means to apply the developed hydraulic pressure to a raising of the inner mast is possible. Thus, and as shown in FIG. 9 a hydraulic cylinder 82 is mounted like the cylinder 32 of FIG. 2 and serves to project a rod 83 in response to the admission of hydraulic fluid under pressure thereto. The upper end of the rod 83, however, instead of directly contacting the upper end of the inner mast carries a sprocket wheel 84 over which extends a chain 85. One end of the chain 85 is connected to a lug 86 stationarily mounted to the bottom of the outer mast. The other end of the chain is connected to the lower end of the inner mast here indicated at 87. The arrangement which may be made to be one multipliying the rate of extension of the inner mast in relation to the rate of extension of the rod 83, may be used to achieve a more convenient and facile positioning of the elevator mechanism with less required movement of the hydraulic actuator.

According to a feature of the mast construction and operation, in either of the embodiments of FIGS. 2 and 9, the lower end of the inner mast is extensible below the lower end of the outer mast. In consequence, the lift arm assembly is enabled to descend below the lateral plane of the bottom ends of the stationary masts 24 and 25 to a position of rest on ground level. Broken line showings in each of FIGS. 2 and 9 indicate the manner in which the inner mast extends beneath the outer mast in a lowering of the lift arm assembly to its maximum extent. As shown in FIG. 12, near its lower end the inner mast 34 is cut away to define a clearance area 88. In this manner interference by the plate 30 on the lower end of the outer mast with descent of the inner mast is avoided and freedom of movement of the inner mast to a downward, relatively extended position is possible. In a nonoperating position of the parts, the inner mast is raised or retracted to be enclosed within the outer mast. The hydraulic mechanism is not required to sustain the parts in this relatively elevated position, however, this load being borne by the supports 52 and 53 as described previously. The inner masts have a long bearing in the outer masts enabling accurate, easy adjustment thereof. The open upper ends of the outer mast allow the inner masts to project therefrom, giving the inner masts a wide range of positionable motion despite their elongated bearings. FIGURE'13 shows the position of the parts when the arms 43 are in their lowermost position. FIG- URE 14 shows the relationship of the parts when the arms 43 are in a raised position.

The assembly of channel pieces 59 and rollers 61 is removably secured to the truck, in the manner of the brackets 58, by means of bolts 89, the heads of which engage the channels 59 within the slotted openings 90.

From the above description it will be apparent that there is thus provided a device of the character described possessing the particular features of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not limited to the specific features shown, but that the means and construction herein disclosed comprise but one of several modes of putting the invention into effect, and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

Having thus described my invention, I claim:

1. In the art of material handling, the combination of a transport vehicle providing a storage compartment having sidewalls and an opening thereto, a pair of laterally spaced apart vertically extending masts stationarily mounted to said vehicle, one on either side of said opening, said masts having a channel-like configuration with a slotted opening of longitudinal extent on one side thereof, said masts being disposed with the said one sides thereof in opposing relation across said opening, an inner mast slidably received in each of said pair of masts for selective vertical positioning therein, a plate along side each of said pair of masts and adjacent thereto, each plate having a flange portion received in the said slotted opening of the adjacent stationary mast and secured to the inner mast therein, and a pallet supporting guide arm connected to each of said plates adapted to project rearwardly of the vehicle, each of said arms having anti-friction rollers including rollers overlying said plate in laterally spaced relation to said flange thereon, said arms being in a common vertical plane with respective guides to be aligned therewith upon appropriate vertical positioning of said inner masts whereby said guides form direct continuation of said arms, and a horizontal tie bar connected at its ends to respective plates at locations spaced laterally inward from said guide arms.

2. A combination according to claim 1, characterized in that said inner masts are elongated for long bearings in said stationary masts, the opposite ends of the latter being open to allow said inner masts to assume upper and lower relative projecting positions.

3. A combination according to claim 2, characterized by hydraulic cylinder means mounted in respective stationary masts to engage and vertically position the inner masts therein, said inner masts being formed at their lower ends to move relatively to said cylinder means, the opposite ends of said stationary masts being open to allow said inner masts to assume upper and lower relatively projecting positions.

4. In the art of material handling, the combination of a transport vehicle providing a storage compartment having an opening, a pair of laterally spaced apart vertically extending masts stationarily mounted to said vehicle, one on either side of said opening, said masts having sides in opposing relation to one another across said opening, a movable mast connected to each of said stationarily mounted masts for relative vertical sliding motion, pallet supporting guide arms connected to respective movable masts to lie in outwardly projecting relation to the vehicle in planes near said opposing sides of said stationarily mounted masts, at least one longitudinally arranged set of parallel guides in said compartment terminating at their one ends within said opening thereto, positioned to be respectively coaxial with and provide direct extensions of said guide arms on elevation of said guide arms to a plane common thereto, and thrust means fixedly mounted to said stationarily mounted masts providing said relative sliding motion of said movable masts and projection thereof relative said stationarily mounted masts, said movable masts being cut away to avoid interference with said thrust means whereby to extend in embracing, by-passing relation to said thrust means to allow relative projections thereof.

5. In the art of material handling, the combination of transport vehicles providing a storage compartment having an opening, interiorly extending guide rails in said storage compartment terminating at their one ends at opposing marginal locations at said opening, a pair of laterally spaced apart vertically extending masts stationarily mounted to said vehicle, one on either side of said opening, said masts having a hollow open ended configuration and being slotted on respectively opposing sides, a movable mast in each stationarily mounted mast reciprocable vertically therein, a plate arranged in adjacent relation to the said slotted side of each stationarily mounted mast and having means projecting therethrough to engage the associated movable mast therein, and a guide arm mounted to each of said plates located in a vertical plane common to a respective one of said guide rails whereby to be aligned with said guide rail upon appropriate vertical positioning of said movable masts, said guide arms being adapted to extend outwardly of the vehicle as aligned continuations of said guide rails, said mounting plates spacing said guide rails laterally inward from said stationarily mounted masts and from the margin of said opening to obviate interference with pallets introduced into and removed from said storage compartment by way of said guide arms.

6. A combination according to claim 5, characterized by means based on each of said stationarily mounted masts and extensible relatively thereto to raise and lower the movable mast therein, said movable mast having extremes of operation above and below the open ends of the stationarily mounted masts.

7. In the art of material handling, the combination of a transport vehicle providing a storage compartment having an opening, laterally spaced apart vertically extending masts stationarily mounted to the vehicle, one on either side of said opening, a movable mast mounted to each of said stationarily mounted masts for vertical relative sliding motion, pallet supporting guide arms, one connected to each of said movable masts, at least one set of guide rails in said compartment, said guide arms being in a common vertical plane with respective guide rails so that upon appropriate vertical positioning of said movable masts, said guide arms may be aligned with guide rails to serve as outwardly projecting extensions or continuations thereof, means based on said stationarily mounted masts and extensible and retractable to elevate and to control the lowering of said movable masts, and stop means limiting elevation of said movable masts to a position aligning said guide arms with said guide rails, said movable masts retaining an elevated position engag- 10 ing said stop means by reason of continued thrust applied through said extensible means.

References Cited by the Examiner UNITED STATES PATENTS 2,456,320 12/1948 Repke 214-674 2,530,341 11/1950 Satsky.

2,543,143 2/1951 Wells 296-28.2 2,635,771 4/1953 Black.

2,640,612 6/1953 Barry.

2,655,223 10/ 1953 Villars 1878.59 2,832,435 4/1958 Garapolo 187--10 2,885,221 5/1959 Weeks 280-179 FOREIGN PATENTS 1,108,626 9/1955 France.

683,692 12/ 1952 Great Britain.

GERALD M. FORLENZA, Primary Examiner.

MORRIS TEMIN, HUGO O. SCHULZ, Examiners. 

1. IN THE ART OF MATERIAL HANDLING, THE COMBINATION OF A TRANSPORT VEHICLE PROVIDING A STORAGE COMPARTMENT HAVING SIDEWALLS AND AN OPENING THERETO, A PAIR OF LATERALLY SPACED APART VERTICALLY EXTENDING MASTS STATIONARILY MOUNTED TO SAID VEHICLE, ONE EITHER SIDE OF SAID OPENING, SAID MASTS HAVING A CHANNEL-LIKE CONFIGURATION WITH A SLOTTED OPENING OF LONGITUDINAL EXTENT ON ONE SIDE THEREOF, SAID MASTS BEING DISPOSED WITH THE SAID ONE SIDES THEREOF IN OPPOSING RELATION ACROSS SAID OPENING, AN INNER MAST SLIDABLY RECEIVED IN EACH OF SAID PAIR OF MASTS FOR SELECTIVE VERTICAL POSITIONING THEREIN, A PLATE ALONG SIDE EACH OF SAID PAIR OF MASTS AND ADJACENT THERETO, EACH PLATE HAVING A FLANGE PORTION RECEIVED IN THE SAID SLOTTED OPENING OF THE ADJACENT STATIONARY MAST AND SECURED TO THE INNER MAST THEREIN, AND A PALLET SUPPORTING GUIDE ARM CONNECTED TO EACH OF SAID PLATES ADAPTED TO PROJECT REARWARDLY OF THE VEHICLE, EACH OF SAID ARMS HAVING ANTI-FRICTION ROLLERS INCLUDING ROLLERS OVERLYING SAID PLATE IN LATERALLY SPACED RELATION TO SAID FLANGE THEREON, SAID ARMS BEING IN A COMMON VERTICAL PLANE WITH RESPECTIVE GUIDES TO BE ALIGNED THEREWITH UPON APPROPRIATE VERTICAL POSITIONING OF SAID INNER MASTS WHEREBY SAID GUIDES FORM DIRECT CONTINUATION OF SAID ARMS, AND A HORIZONTAL TIE BAR CONNECTED AT ITS ENDS TO RESPECTIVE PLATES AT LOCATIONS SPACED LATERALLY INWARD FROM SAID GUIDE ARMS. 